The Crazed Butt-Stabber is what Mark coins the main antagonist of the game "Intruder". He roams the house where the game takes place, hiding in the shadows, searching for the player in order to kill him. Markiplier plays as him in the game "Calm Time."

Markiplier had previously uploaded the video for Electronic Super Joy earlier that day, in which the player was on a quest to get revenge for his butt. Mark became so obsessed with butts that day, and it carried over into Intruder.

Mark nicknamed him "The Crazed Butt-Stabber" because he stalks his victims, then he stabs them in the butt until they die. According to Markiplier, his butt is the only weakness.

"Ok here's the scene, you're driving home from work all safe and sound trying to get back to your bowl of popcorn and your episode of Glee when you here a crackle on the radio -THE CRAZED BUTT STABBER HAS ESCAPED FROM ARKHAM ASYLUM- but it's not bad, he cant be in your area. You open your front door going "I can't be stabbed multiple times in the butt!" but TOO LATE he's in your house and you die, dead from multiple stab wounds in the butt!" - Markiplier

Appearance(s)

The Crazed Butt-Stabber is a shadowy man wielding a knife. His face is fully shown at the end of the game.
He also appears to be immortal, as he was shot in the head and survived.